M2 Freightliner Ambulance Conversion Project. 2007 Crew Cab

Hey Oz, can you tell me (us) more about your bathroom plans? I've got the same plan, for that same space. For those not following closely, we'll be doing what Bevan did... remove the left rear O2 bottle storage and turn that into a shower with a "composting" toilet. And that leads to my question, since you're a bit ahead of us. Are you going to cover the Nature's Head you got, to keep shower water out of it? Or do they not need that? We had planned to put a bench in our shower, and build the composting toilet into that. My thought was to have a fold-down cover that would shed shower water and keep it out of the poo bin. But that toilet you ordered would certainly be an easier option. Teach me, master!
 
We drape a corner of our shower curtain over our Nature's Head toilet. We have replaced the seal since original but choose to make sure no water gets at the "compost". It did once and I vowed I would never let it happen again, LOL.
Ward
 

Ozrockrat

Expedition Leader
Ross! Since I am fundamentally FDL (fat dumb and lazy) I will hold off on any covers etc until the need is proven. Saying that, we are considering putting a shower curtain in to keep the water off the toilet and off the concertina door. If done with a pivot it could also flip to provide an outside screen if we wanted to shower outside (think beach etc ). This will probably not happen this year because after getting it usable and doing a month or so working out of the truck in Colorado we will be starting on 4WD.

As far as the shower I will need to do up a plumbing diagram but the general idea is dual shower heads (rain overhead and Oxygenics hand shower).

These will be fed through a European style thematic mixer (set the temp and then just turn the water on/off).

Also even though we will be 5’ from an instant heat water source I am considering running the extra water line back to the tank and having a diverted valve off the hot water source. (Such as the diverter that someone listed on here). This will cover off 3 items.
1- make sure we have hot water to the mixer before turning the shower on (less wasted water and less gray water)
2- use the diverter to heat the pipes feeding the shower/sink in times of extreme cold.
3- use the diverter to heat the water in the water tank by continuously circulating it through the water heater in times of extreme cold.

Now saying that remember I am an Aussie who lives in hell (Phoenix). Since our initial travel for the next 5 years will be vacation only we will use the manual climate control of picking where we are based on the seasons (somewhere 45 to 80). So this is only for those times were we get caught in extreme cold while traveling.

Now I understand that people who live in colder climates need to protect their vehicles during storage. But hopefully we will not be in that situation.

We will have the ability to preheat the engine and all the external cabinets along with the internal cab and box with the diesel water heater.

Now I have just about worn out my thumbs typing this on my phone I will leave it to you guys to ask any specific questions.
 

Ozrockrat

Expedition Leader
but choose to make sure no water gets at the "compost". It did once and I vowed I would never let it happen again, LOL.
Ward
In the thread I had going about where to buy the Nature’s Head there was a couple of suggestions about drilling holes to help reduce the possibility of that happening. If I was smart enough I would link across to it but my phone is smarter than I am and I cannot work out how.
 

java

Expedition Leader
Run the diverter line back to the tank. Easy to do now, hard later! Mine is 2.5' from the heater to the faucet and takes it 20 seconds to get hot (less for warm ish). My heater is directly under the sink in the cabinet there, couldn't get any closer.

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Ozrockrat

Expedition Leader
For use in the wet room I drilled 2 small holes in the corners of the box lip outside of the weather stripping. This will allow any shower water to drain outside the container. Also drill some large drain holes in the urine container-holder base.
From the other thread.
 

Ozrockrat

Expedition Leader
Run the diverter line back to the tank. Easy to do now, hard later! Mine is 2.5' from the heater to the faucet and takes it 20 seconds to get hot (less for warm ish). My heater is directly under the sink in the cabinet there, couldn't get any closer.

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What do you think about running all the water lines in the same insulation so that the diverted water can heat the lines in extreme conditions? I may have a set of water lines running semi exposed under the box from side to side.
 

java

Expedition Leader
Run the diverter line back to the tank. Easy to do now, hard later! Mine is 2.5' from the heater to the faucet and takes it 20 seconds to get hot (less for warm ish). My heater is directly under the sink in the cabinet there, couldn't get any closer.

Sent from my SM-G950U using Tapatalk
What do you think about running all the water lines in the same insulation so that the diverted water can heat the lines in extreme conditions? I may have a set of water lines running semi exposed under the box from side to side.
I think it's a good idea, you could go as far as a heater line looped though with them as well. But I use my truck sub freezing often so my needs may be a bit different! :)

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Ozrockrat

Expedition Leader
Run the diverter line back to the tank. Easy to do now, hard later! Mine is 2.5' from the heater to the faucet and takes it 20 seconds to get hot (less for warm ish). My heater is directly under the sink in the cabinet there, couldn't get any closer.

Sent from my SM-G950U using Tapatalk
What do you think about running all the water lines in the same insulation so that the diverted water can heat the lines in extreme conditions? I may have a set of water lines running semi exposed under the box from side to side.
I think it's a good idea, you could go as far as a heater line looped though with them as well. But I use my truck sub freezing often so my needs may be a bit different! :)

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Hmm I could run the heating lines in the same insulation for the boxes on the passengers side. Probably all going to be pex anyway. I had planned on color coding with the red, blue and white so I may need to check alternative sizes or types to distinguish between heating (glycol) and water. I could always run copper heating lines across under the body to distinguish between them.
 

java

Expedition Leader
Run the diverter line back to the tank. Easy to do now, hard later! Mine is 2.5' from the heater to the faucet and takes it 20 seconds to get hot (less for warm ish). My heater is directly under the sink in the cabinet there, couldn't get any closer.

Sent from my SM-G950U using Tapatalk
What do you think about running all the water lines in the same insulation so that the diverted water can heat the lines in extreme conditions? I may have a set of water lines running semi exposed under the box from side to side.
I think it's a good idea, you could go as far as a heater line looped though with them as well. But I use my truck sub freezing often so my needs may be a bit different! :)

Sent from my SM-G950U using Tapatalk
Hmm I could run the heating lines in the same insulation for the boxes on the passengers side. Probably all going to be pex anyway. I had planned on color coding with the red, blue and white so I may need to check alternative sizes or types to distinguish between heating (glycol) and water. I could always run copper heating lines across under the body to distinguish between them.
I like that plan! Best for bulletproof. You should be able to tell which has the glycol from the color in the white pipes, they are transparent ish.

I don't to glycol radiant systems, but we have to use heat pex with water, it has an oxygen barrier to help with corrosion in the system. I would probably use it regardless, but worth looking into.

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The PEX with the oxygen barrier is orange and should be used with glycol. Running a heater line with the domestic water will work but the domestic water will be warm and in sub zero you will always have to keep the heat on. Far better to keep all domestic water lines inside the vehicles heated envelope.
 

Ozrockrat

Expedition Leader
Far better to keep all domestic water lines inside the vehicles heated envelope.
Where ever possible all water lines and tanks will be inside the heated envelope. But the transition from side to side involves either running it in the ceiling cavity which is an aluminum skin with some insulation or running it under the floor.

I am leaning towards under floor for the following reasons.
1- while the likely hood of failure is on par with in the ceiling the consequence of failure is much smaller. And a lot easier to repair.
2- having fought the battle once trying to get pex through the ceiling cavity it is a real PITA and quite possibly impossible to do without stripping the ceiling.
 

java

Expedition Leader
The PEX with the oxygen barrier is orange and should be used with glycol. Running a heater line with the domestic water will work but the domestic water will be warm and in sub zero you will always have to keep the heat on. Far better to keep all domestic water lines inside the vehicles heated envelope.
Not necessarily orange, I have used lots of Red and white (clear) PEX with 02 barrier. I'm guessing it depends on brand. I prefer the Wirsbo/Uponor myself.

Go figure. I have never seen PEX heating pipe. Definitely not on the shelf at my local Home Depot in Phoenix. I wonder why not
Yeah HD stocks Sharkbite brand (around me anyway) which IMO is the worst stuff. What connection system do you plan to use? There are a few different types and they each have their own flavor pf "PEX".


I prefer the Uponor system, it expands the pipe for the fitting to fit inside of, this makes for nearly full flow fittings, rather than necking down as some of the crimp systems do. It does require a special tool, but you can likely rent them (or buy a electric one for ~$350), but I have had nearly no leak issues. The fittings come in plastic or brass too.




Can you run across the floor inside somewhere? That is what I ended up doing, right across the front edge of the box, where the pass thru to the cab is. The pass through trim will cover the exposed pipe there. I only needed to get cold through though.
 
Like Java, I like the Uponor system. It's a bit tricky to use, as you have to put on the sleeve and then expand the pipe end with the special tool just right (making absolutely sure the pipe and sleeve are all the way on the expansion head). I had to go through training, when I was plumbing in a prior life, to get the tool from our plumbing supply house locally... and the tool wasn't cheap. So, renting would be great if that's an option. Granted that was a long time ago, so training might not be a thing now.

On a related note, the PEX tubing is pretty darned resistant to freeze damage. The fittings are another matter, so definitely keep those inside, but I've seen PEX freeze and swell and not suffer any permanent damage. Not that you want any of your pipe to freeze... but, it may not be the end of the world if it's the tube itself and not the fittings (which will crack or split if frozen).

We'll definitely be using PEX for our plumbing (tanks and pump are on the way now!).